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Cat MM55SR excavator

G'day all
A local contractor in town has purchased a MM55SR painted up in Cat colours, but I think it may be a Mitsubishi, either way it is a grey import as E1G00xx prefix doesn’t come up as a good serial # with Cat dealer. My mate needs to find a few parts, his biggest problem is that the hyd don’t work when levers are used, but if you move control valve direct they with work. The electronic hand control system seems to be the problem, anyone had any experience with these machines or this problem?

A friend of me who owns a mitsubishi 5 ton excavator here in my country, replaced the electronic hand control to usual hydraulic controls because he could not find any parts. Of course he paid enough money...
I also have a c a t graymm and the only way to find parts is to use serials from cat catalogue.
So, you have to find out the similar to yours cat machine and match the parts serial. But this is also riski because serials do not always fit to the gray machines.

G'day all
A local contractor in town has purchased a MM55SR painted up in Cat colours, but I think it may be a Mitsubishi, either way it is a grey import as E1G00xx prefix doesn’t come up as a good serial # with Cat dealer. My mate needs to find a few parts, his biggest problem is that the hyd don’t work when levers are used, but if you move control valve direct they with work. The electronic hand control system seems to be the problem, anyone had any experience with these machines or this problem?

thanks in advance

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That is a rebranded mitsubishi...as for the problem,is there a bad switch in the pilot enable lever perhaps?

Does anyone know where you can get parts for an MM55SR? Cat is no help and have not been able to find any parts. I'd love to have any service info anyone has. I have a schematic for the MM55SR if anyone needs it.

I own a mm40sr and i have the same problem
have found another thread on "mm30sr" full of people withthe same issues. as far as i can tell they are very simmilar electronicly. I have some error code sheets for these machines but am still at a loss for parts or help.

that would be great. send me your email eddress i will forward them to you. & i would be very greatfull to know more about were to solder a new earth wire to on the circuit board. a photo or instruction on the process would be fantastic.

that would be great. send me your email eddress i will forward them to you. & i would be very greatfull to know more about were to solder a new earth wire to on the circuit board. a photo or instruction on the process would be fantastic.

Does anyone know where you can get parts for an MM55SR? Cat is no help and have not been able to find any parts. I'd love to have any service info anyone has. I have a schematic for the MM55SR if anyone needs it.

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Can you send me the schematic foor the MM55SR. I have a problem with my machine

We have been supplying controller replacement kits for the MM55SR since 2009. The controller is a non-computer based box, converting the Mitsubishi joystick signals, matched to control the proportional valves. The retrofit is simple, basically bypassing the old loom and using only the existing valve and joystick connections. Please contact me info@imdynamics.com.au for details

Does anyone know where you can get parts for an MM55SR? Cat is no help and have not been able to find any parts. I'd love to have any service info anyone has. I have a schematic for the MM55SR if anyone needs it.

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Graham any chance i could get a copy of the schematic? I have the same problem with a MM55SR that the joystick controls wont work.

Does anyone know where you can get parts for an MM55SR? Cat is no help and have not been able to find any parts. I'd love to have any service info anyone has. I have a schematic for the MM55SR if anyone needs it.

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Graham, we would very much appreciate a copy of an electrical schematic for the mm55sr if you can help thanks.

We have been supplying controller replacement kits for the MM55SR since 2009. The controller is a non-computer based box, converting the Mitsubishi joystick signals, matched to control the proportional valves. The retrofit is simple, basically bypassing the old loom and using only the existing valve and joystick connections. Please contact me info@imdynamics.com.au for details

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glad i finally found other people with the same problem, can you email me with a price and availability to the U.S. thanks kevin.